This amount includes applicable customs duties, taxes, brokerage and other fees. This amount is subject to change until you make payment. For additional information, see the Global Shipping Program terms and conditions- opens in a new window or tabThis amount includes applicable customs duties, taxes, brokerage and other fees. This amount is subject to change until you make payment. If you reside in an EU member state besides UK, import VAT on this purchase is not recoverable. For additional information, see the Global Shipping Program terms and conditions- opens in a new window or tab

ABOUT QUARTZ: Quartz is the most common mineral in the continental crust, and the one with the simplest chemical formula: silicon dioxide or SiO2. Quartz is so common in crustal rocks that it's more notable when quartz is missing than when it's present. Quartz is an old German word that originally meant something like hard or tough.

Special Quartz Varieties

The pretty crystals and vivid colors you'll see in jewelry and in rock shops are scarce. Here are some of those precious varieties:

Where Quartz Is Found

Quartz is perhaps the most typical mineral of the planet Earth. In fact, one test of a meteorite, if you think you've found one, is to be sure it doesn't have any quartz. But more than that, quartz is typical of the continents. Geologic processes have concentrated it there.

Quartz is found in most geologic settings, but it most typically forms sedimentary rocks like sandstone. This is no surprise when you consider that nearly all the sand on Earth is almost exclusively grains of quartz. Under mild heat and pressure conditions, geodes can form in sedimentary rocks that are lined with crusts of quartz crystals deposited from underground fluids.

In igneous rocks, quartz is the defining mineral of granite. When granitic rocks crystallize deep underground, quartz is generally the last mineral to form and it usually has no room to form crystals. But in pegmatites quartz can sometimes form very large crystals, as long as a meter. Crystals also occur in veins associated with hydrothermal activity in the shallow crust.

In metamorphic rocks such as gneiss, quartz becomes concentrated in bands and veins. In this setting its grains do not take their typical crystal form. Sandstone, too, turns into a massive quartz rock called quartzite.

What Quartz Means

Among the common minerals, quartz is the toughest and most inert. It makes up the backbone of good soil, providing mechanical strength and holding open pore space between its grains. Its superior hardness and resistance to dissolution are what make sandstone and granite endure. Thus you could say that quartz holds up the mountains.

Prospectors are always alert to veins of quartz because these are signs of hydrothermal activity and the possibility of ore deposits.

To the geologist, the amount of silica in a rock is a basic and important bit of geochemical knowledge. Quartz is a ready sign of high silica, for example in a rhyolite lava.

When found in abundance, quartz always points to a continental rock because the tectonic processes that have built the Earth's continents favor quartz. (For more, see About the Earth's Crust.) But quartz helps itself by being hard, stable and low in density. As it moves through the tectonic cycle of erosion, deposition, subduction and magmatism, quartz lingers in the uppermost crust and always comes out on top.

also have matching NECKLACES. Please see our other unique, one-of-a-kind creations!

We are THRILLED to serve you and help you have a fantastic eBay experience!!!

The choice is yours. PayPal Credit gives you the flexibility to pay for your purchases now or over time with one of our special financing offers. Please note, if your purchase qualifies for a special financing offer:

Interest will be charged on your account from the posting date (which is usually within a few days after the purchase date) if the purchase balance is not paid in full within financing period. Subject to credit approval. See terms - opens in a new window or tab

Seller's payment instructions

Please pay within three days, or you may make other arrangements with me. I'm very flexible :)

By submitting your bid, you are committing to buy this item from the seller if you are the winning bidder. You have read and agree to the Global Shipping Program terms and conditions - opens in a new window or tab. Import charges previously quoted are subject to change if you increase you maximum bid amount.

By clicking Confirm, you commit to buy this item from the seller if you are the winning bidder.

By clicking Confirm, you are committing to buy this item from the seller if you are the winning bidder and have read and agree to the Global Shipping Program terms and conditions - opens in a new window or tab. Import charges previously quoted are subject to change if you increase you maximum bid amount.